獲取類型錯誤

Question

當我提交表單請求時，出現錯誤[TypeError: object is not a function]。 這裏是我的貓鼬代碼：hiren-conf.js

var auth = require('../auth.js'); 
var mongoose = require('mongoose'); 

mongoose.connect(auth['mongodb']); 

var authSchema = new mongoose.Schema({ 
    tag: String, 
    email: String, 
    username: String, 
    createdOn: Date, 
    updatedOn: { type: Date, default: Date.now }, 
    url: String, 
    password: String, 
    icon: String 
}); 

var masterPass = new mongoose.Schema({ 
    hash : String, 
    tag : String, 
    state: { type: String, default: false} 
}); 

exports.auth = mongoose.model('Auth', authSchema); 
exports.master = mongoose.model('Master', masterPass); 

和database.js代碼：

var mongoose = require('mongoose'); 
var auths = require('../model/hiren-conf'); 

exports.create = function(req){ 
    var instance = new auths(); 
    if(req.body.tag && req.body.email){ 
     auths.findOne({ 'tag' : req.body.tag , 'email' : req.body.email}, function(err , duplicate){ 
      if (!err){ 
       if(!duplicate){ 
        instance.tag = req.body.tag; 
        instance.email = req.body.email; 
        instance.username= req.body.username; 
        instance.createdOn = Date.now(); 
        instance.url = req.body.url; 
        instance.password = req.body.password; 
        instance.save(function(err){ 
         if(!err) console.log('Saved'); 

        }); 
        return "Save"; 

      }  else return "Duplicate"; 
     } else console.log(err); 
     }); 

     } 

    }; 

可能存在exports.auth一個問題，但我不知道。任何想法如何解決這個問題？